[Case report on testicular tumors in non-twin siblings]

A case report of testicular tumors in non-twin siblings is presented. A 42-year-old male was admitted to Kansai Electric Power Hospital with the complaint of swelling of the left scrotal contents. Left radical orchiectomy was performed with the diagnosis of a left testicular tumor. Histological examination revealed a seminoma of the left testis. Fifteen years later, his 43-year-old younger brother was admitted to Osaka University Hospital with the complaint of painless swelling of the left scrotal contents. Left radical orchiectomy was carried out with the diagnosis of a left testicular tumor. Histological examination showed a seminoma of the left testis. The former patient had a history of a scrotal trauma, but there was no history of orchitis or cryptorchism in these two siblings. To our knowledge, there have been reported 44 sets of testicular tumors in siblings. Eleven of these sets appeared in twins, while the other 33 sets were described in non-twin siblings. We discussed the 45 cases including our case of testicular tumors in siblings.